Got a set of three cheap studio strobes (Neewer c300). They came with a single rf trigger, and they can act as optical slaves.

They work just fine when using the radio trigger, the secondary strobe fires from the primarie's flash, and contributes to the shot normally. However when i use the camera's own flash as master, the strobe fires, but contributes nothing to the shot, because it is out of sync.

Confused by this to say the least. It sees the camera flash, and fires, but the shutter is closed by then. Yet when it triggers off its companion flash (which syncs via rf) it syncs into the shot.

I have a nissin speedlight, and can get it to fire off camera via the ittl cmd mode fine, but when i power it off, then turn the studio strobe on (ie change nothing in the camera settings), the strobe fires but not in sync.

The strobes are "dumb" units in that all they do is fire at a set power level. iTTL Speedlights can adjust power as needed based on the "intellegent Through The Lens" measurement of the reflected light from preflashes sent just before the picture is taken.

Problem? The iTTL preflashes fire the strobe before the shutter opens. The strobe(s) can be triggered by the flash from one other (radio controlled) strobe, because there's only one flash; no preflashes.

Your Nissin flash fires in sync because it's designed to be controlled by the Nikon Creative Light System (CLS), and so it "understands" the pulse language of the camera's flash and knows to fire at the right time(s).

The command-and-control and metering preflashes happen so fast that they may appear to be one and the same as the exposure flash, but they're not; you can see this by setting a slow shutter speed and rear-curtain sync: the preflashes will happen before the shutter opens, then there will be a delay as the exposure takes place, then -- just before the second curtain closes -- the main flash pulse will go off.

Bfindlay wrote:
They work just fine when using the radio trigger, the secondary strobe fires from the primarie's flash, and contributes to the shot normally. However when i use the camera's own flash as master, the strobe fires, but contributes nothing to the shot, because it is out of sync.

Suggestions?

Set your built-in flash to Manual at a low (or suitable output) and your remotes will fire in sync. They won't work in TTL unless you trigger from your radio. Using an SB on your hotshoe and taking a sync from that to your radio will retain TTL sync as the signal flashes are ignored and only the sync signal is utilised. Your second remote flash will also require a radio receiver in this case.

Bfindlay wrote:
Got it working. Switched the menu from cmd mode to manual and all is golden!

Yep; manual power in wireless mode still sends command pulses to the slaves to tell them what power to use, so that will trigger the strobes prematurely; but manual non-wireless mode is just the single on-camera pop, so that'll work...with Nikons -- Canon's pop-ups are always in ETTL mode, so you can't get full manual without mounting a Speedlite in the hot shoe.

BTW, if you don't want the light from the pop-up to be visible at all in your shots, Nikon makes this handy-dandy little device:

The infra-red portion of the flash gets through and triggers the strobes, but the visible portion is blocked. Best of all, you can use full power for maximum reach to your strobes without having to worry about how it will affect your subject.

BrianO wrote:BTW, if you don't want the light from the pop-up to be visible at all in your shots, Nikon makes this handy-dandy little device:

Is there any Nikon body whose popup flash can act as a commander but cannot be controlled and told not to contribute to the exposure? On a D300, you can just instruct the flash not to fire during the exposure, and only to command and trigger the other flashes. Is that impossible on the D200 (pictured)?

BrianO wrote: BTW, if you don't want the light from the pop-up to be visible at all in your shots, Nikon makes this handy-dandy little device:

Ian Ivey wrote: Is there any Nikon body whose popup flash can act as a commander but cannot be controlled and told not to contribute to the exposure? On a D300, you can just instruct the flash not to fire during the exposure, and only to command and trigger the other flashes. Is that impossible on the D200 (pictured)?

The issue is that the final "Fire now!" pulse must happen after the shutter opens, and so even if it is very dim, it can sometimes be seen if there is a reflective object in the background, or if the camera-to-subject distance is very short.

And of course in the OP's case, where he wants to use the pop-up in Manual mode to trip strobes, the pop-up can't be set not to fire because...well...it won't. Using the IR filter accessory will allow the pop-up to trigger the strobes without contributing to the exposure.